1 files changed, 80 insertions, 0 deletions
diff --git a/drivers/firmware/efi/libstub/loongarch.c b/drivers/firmware/efi/libstub/loongarch.c
new file mode 100644
index 0000000000..0e0aa6cda7
--- /dev/null
+++ b/drivers/firmware/efi/libstub/loongarch.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Author: Yun Liu <liuyun@loongson.cn>
+ *         Huacai Chen <chenhuacai@loongson.cn>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#include <asm/efi.h>
+#include <asm/addrspace.h>
+#include "efistub.h"
+
+typedef void __noreturn (*kernel_entry_t)(bool efi, unsigned long cmdline,
+					  unsigned long systab);
+
+efi_status_t check_platform_features(void)
+{
+	return EFI_SUCCESS;
+}
+
+struct exit_boot_struct {
+	efi_memory_desc_t	*runtime_map;
+	int			runtime_entry_count;
+};
+
+static efi_status_t exit_boot_func(struct efi_boot_memmap *map, void *priv)
+{
+	struct exit_boot_struct *p = priv;
+
+	/*
+	 * Update the memory map with virtual addresses. The function will also
+	 * populate @runtime_map with copies of just the EFI_MEMORY_RUNTIME
+	 * entries so that we can pass it straight to SetVirtualAddressMap()
+	 */
+	efi_get_virtmap(map->map, map->map_size, map->desc_size,
+			p->runtime_map, &p->runtime_entry_count);
+
+	return EFI_SUCCESS;
+}
+
+unsigned long __weak kernel_entry_address(unsigned long kernel_addr)
+{
+	return *(unsigned long *)(kernel_addr + 8) - VMLINUX_LOAD_ADDRESS + kernel_addr;
+}
+
+efi_status_t efi_boot_kernel(void *handle, efi_loaded_image_t *image,
+			     unsigned long kernel_addr, char *cmdline_ptr)
+{
+	kernel_entry_t real_kernel_entry;
+	struct exit_boot_struct priv;
+	unsigned long desc_size;
+	efi_status_t status;
+	u32 desc_ver;
+
+	status = efi_alloc_virtmap(&priv.runtime_map, &desc_size, &desc_ver);
+	if (status != EFI_SUCCESS) {
+		efi_err("Unable to retrieve UEFI memory map.\n");
+		return status;
+	}
+
+	efi_info("Exiting boot services\n");
+
+	efi_novamap = false;
+	status = efi_exit_boot_services(handle, &priv, exit_boot_func);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	/* Install the new virtual address map */
+	efi_rt_call(set_virtual_address_map,
+		    priv.runtime_entry_count * desc_size, desc_size,
+		    desc_ver, priv.runtime_map);
+
+	/* Config Direct Mapping */
+	csr_write64(CSR_DMW0_INIT, LOONGARCH_CSR_DMWIN0);
+	csr_write64(CSR_DMW1_INIT, LOONGARCH_CSR_DMWIN1);
+
+	real_kernel_entry = (void *)kernel_entry_address(kernel_addr);
+
+	real_kernel_entry(true, (unsigned long)cmdline_ptr,
+			  (unsigned long)efi_system_table);
+}